(57) Silica glass powders are prepared by mixing a silicic acid ester, water in an amount equal to or larger than 0.5 times of gram equivalent of an alkoxy group of the silicic acid ester and siliceous particles and dispersing the siliceous particles which have particle sizes of larger than 400 µ m in an amount of less than 10% by weight and particle sizes of less than 20 µ m in an amount of less than 50% by weight and which are dispersed in an amount equal to or larger than 10% by weight of the weight of silica prepared by roasting the silicic acid ester in the same amount as used for the preparation of the mixture, gelling the dispersion to give a gel, drying the gel, and sinterring the dried gel. The silica glass powders of high purity is suitable for varioususes such as raw materials for silica glass products for semiconductor industry and for multicomponent glass for optical communication.